Micro-environment chamber and system for rinsing and drying a semiconductor workpiece

ABSTRACT

In a method for rinsing and drying a semiconductor workpiece in a micro-environment, the workpiece is placed into a rinser/dryer housing. The rinser/dryer housing is rotated by a rotor motor. The rinser/dryer housing defines a substantially closed rinser/dryer chamber. Rinsing and drying fluids are distributed across at least one face of the semiconductor workpiece by the action of centrifugal force generated during rotation of the housing. A fluid supply system is connected to sequentially supply a rinsing fluid followed by a drying fluid to the chamber as the housing is rotated.

[0001] This Application is a Divisional of U.S. patent application Ser.No. 09/041,649 filed Mar. 13, 1998, and now pending, and incorporatedherein by reference.

BACKGROUND OF THE INVENTION

[0002] The semiconductor manufacturing industry is constantly seeking toimprove the processes used to manufacture integrated circuits fromwafers. The improvements come in various forms but, generally, have oneor more objectives as the desired goal. The objectives of many of theseimproved processes include: 1) decreasing the amount of time required toprocess a wafer to form the desired integrated circuits; 2) increasingthe yield of usable integrated circuits per wafer by, for example,decreasing the likelihood of contamination of the wafer duringprocessing; 3) reducing the number of steps required to turn a waferinto the desired integrated circuits; and 4) reducing the cost ofprocessing the wafers into the desired integrated circuit by, forexample, reducing the costs associated with the chemicals required forthe processing.

[0003] One of the most crucial processes in the fabrication ofintegrated circuits involves the rinsing and drying of the semiconductorwafers between various chemical processing steps. During rinsing,de-ionized (DI) water is often used to assist in the removal ofchemicals from the surface of the wafer. After rinsing is completed, thewafer surface must be dried. During the drying step wafer contaminationoften results. Such contamination is due to evaporation of the DI waterdeposits contaminant particles on the wafer surface.

[0004] Various techniques have been proposed for the rinsing and dryingof semiconductor wafers. One technique used to both rinse and dry wafersrelies upon a spin rinser/dryer. Such a system uses a DI rinse waterspray to rinse the wafer. The wafer is spun during the drying stepthereby removing the water from the surface of the semiconductor waferthrough evaporation and the action of centripetal acceleration.

[0005] Other techniques used to dry wafers include the use of IPA vapordryers, full displacement IPA dryers, and other forms of IPA dryers.These IPA dryers rely upon a large quantity of a solvent, such as IPAand other volatile organic liquids, to facilitate drying of thesemiconductor wafer. One limitation of this type of dryer is its use oflarge solvent quantities which are highly flammable and often hazardousto health and environment. Further, these dryer types are often quiteexpensive. Still further, the large quantities of hot solvent are oftenincompatible with certain recessed pattern wafers and may be detrimentalto certain device structures.

[0006] Another drying technique uses hot DI process water to rinse andpromote drying of the semiconductor wafer. Since the DI water is heated,the liquid on the wafer evaporates faster and more efficiently than DIwater at standard ambient temperatures.

[0007] A still further drying technique is known as a Marangoni dryer.In a Marangoni dryer, the wafer is slowly withdrawn from the rinsingliquid in an atmosphere having a vapor that is miscible with the rinsingliquid. As the wafer is withdrawn, a meniscus is formed at the wafersurfaces. The surface tension of the rinsing fluid at the meniscus isreduced as a result of the presence of the vapor. The reduced surfacetension gives rise to a substantially particle free drying process.

[0008] In each of the foregoing processes, one or more wafers aredisposed in an open chamber during the rinsing and/or drying process. Inthe open chamber, the semiconductor wafers are exposed to a large rinsebath and relatively large area of ambient air. Particles thatcontaminate the wafer during the rinsing and drying processes often comedirectly from the rinse water and ambient air. Control of thecontaminants in the rinsing bath and ambient air in these systems isoften difficult and requires rather elaborate filter systems.

[0009] The approach to rinsing and drying of semiconductor wafersprovided by the invention offers greater control of the physicalproperties of the rinsing and drying fluids. Further, wafers may berinsed and dried on an individual basis more quickly when compared tothe drying of an individual wafer using any of the foregoing processes.

SUMMARY OF THE INVENTION

[0010] An apparatus for rinsing and drying a semiconductor workpiece ina micro-environment is set forth. The apparatus includes a rotor motorand a rinser/dryer housing. The rinser/dryer housing is connected to berotated by the rotor motor. The rinser/dryer housing further defines asubstantially closed rinser/dryer chamber therein in which rinsing anddrying fluids are distributed across at least one face of thesemiconductor workpiece by the action of centripetal accelerationgenerated during rotation of the housing. A fluid supply system isconnected to sequentially supply a rinsing fluid followed by a dryingfluid to the chamber as the housing is rotated.

[0011] In accordance with one embodiment of the apparatus, therinser/dryer housing includes an upper chamber member having a fluidinlet opening and a lower chamber member having a fluid inlet opening.The upper chamber member and the lower chamber member are joined to oneanother to form the substantially closed rinser/dryer chamber. Therinser/dryer chamber generally conforms to the shape of thesemiconductor workpiece and includes at least one fluid outlet disposedat a peripheral region thereof. At least one semiconductor workpiecesupport is provided. The support is adapted to support a semiconductorworkpiece in the substantially closed rinser/dryer chamber in a positionto allow distribution of a fluid supplied through the inlet opening ofthe upper chamber member across at least an upper face of thesemiconductor workpiece through centripetal acceleration generated whenthe rinser/dryer housing is rotated. The wafer is further positioned bythe support to allow distribution of a fluid supplied through the inletopening of the lower chamber member across at least a lower face of thesemiconductor workpiece during the rotation through the action ofcentripetal acceleration. The at least one fluid outlet is positioned toallow escape of fluid from the rinser/dryer chamber through action ofcentripetal acceleration.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0012]FIG. 1 is a cross-sectional view of a rinser/dryer housing and arotor assembly constructed in accordance with one embodiment of theinvention.

[0013]FIG. 2 is an exploded view of a further embodiment of arinser/dryer housing constructed in accordance with the teachings abovethe present invention.

[0014]FIG. 3 is a top plan view of the rinser/dryer housing of FIG. 2when the housing is in an assembled state.

[0015]FIG. 4 is a cross-sectional view of the rinser/dryer housing takenalong line IV-IV of FIG. 3.

[0016]FIG. 5 is a cross-sectional view of the rinser/dryer housing takenalong line V-V of FIG. 3.

[0017]FIG. 6 is a cross-sectional view of the rinser/dryer housing takenalong line VI-VI of FIG. 3.

[0018]FIGS. 7A and 7B are cross-sectional views showing the rinser/dryerhousing in a closed state and connected to a rotary drive assembly.

[0019]FIGS. 8A and 8B are cross-sectional views showing the rinser/dryerhousing in an open state and connected to a rotary drive assembly.

[0020]FIG. 9 illustrates one embodiment of an edge configuration thatfacilitates mutually exclusive processing of the upper and lower wafersurfaces in the rinser/dryer housing.

[0021]FIG. 10 illustrates an embodiment of the rinser/dryer housingemployed in connection with a self-pumping recirculation system.

[0022]FIGS. 11 and 12 are schematic diagrams of exemplary processingtools that employ the rinser/dryer of the present invention.

[0023]FIG. 13 illustrates a batch wafer rinser/dryer constructed inaccordance with the principles of the present invention.

[0024]FIG. 14 is a schematic diagram of one embodiment of a fluid supplysystem that may be used to supply rinsing and drying fluids to therinser/dryer.

DETAILED DESCRIPTION OF THE INVENTION

[0025]FIG. 1 is a cross-sectional view of one embodiment of arinser/dryer, shown generally at 10, constructed in accordance with theteachings of the present invention. The embodiment of the rinser/dryer10 of FIG. 1 is generally comprised of a rotor portion 15 and arinser/dryer housing 20. The rotor portion 15 includes a plurality ofsupport members 25 that extend downwardly from the rotor portion 15 toengage the rinser/dryer housing 20. Each of the support members 25includes a groove 30 that is dimensioned to engage a radially extendingflange 35 that extends about a peripheral region of the rinser/dryerhousing 20. Rotor portion 15 further includes a rotor motor assembly 40that is disposed to rotate a hub portion 45, including the supportmembers 25, about a central axis 47. Rinser/dryer housing 20 is thussecured for co-rotation with hub portion 45 when support members 25 areengaged with flange 35. Other constructions of the rotor portion 15 andthe engagement mechanism used for securement with the rinser/dryerhousing 20 may also be used.

[0026] The rinser/dryer housing 20 of the embodiment of FIG. 1 defines asubstantially closed rinser/dryer chamber 50. Preferably, thesubstantially closed rinser/dryer chamber 50 is formed in the generalshape of the workpiece 55 and closely conforms with the surfaces of theworkpiece. The specific construction of FIG. 1 includes an upper chambermember 60 having an interior chamber face 65. The upper chamber member60 includes a centrally disposed fluid inlet opening 70 in the interiorchamber face 65. The specific construction also includes a lower chambermember 75 having, an interior chamber face 80. The lower chamber member75 has a centrally disposed fluid inlet opening 85 in the interiorchamber face 80. The upper chamber member 60 and the lower chambermember 75 engage one another to define the rinser/dryer chamber 50. Theupper chamber member 60 includes sidewalls 90 that project downward fromthe interior chamber face 65. One or more outlets 100 are disposed atthe peripheral regions of the rinser/dryer chamber 50 through thesidewalls 90 to allow fluid within the chamber 50 to exit therefromthrough centripetal acceleration that is generated when the housing 20is rotated about axis 47.

[0027] In the illustrated embodiment, the workpiece 55 is a generallycircular wafer having upper and lower planar surfaces. As such, therinser/dryer chamber 50 is generally circular in plan view and theinterior chamber faces 65 and 80 are generally planar and parallel tothe upper and lower planar surfaces of the workpiece 55. The spacingbetween the interior chamber faces 65 and 80 and the upper and lowerplanar surfaces of the workpiece 55 is generally quite small. Suchspacing is preferably minimized to provide substantial control of thephysical properties of a rinsing/drying fluid flowing through theinterstitial regions.

[0028] The wafer 55 is spaced from the interior chamber face 80 by aplurality of spacing, members 105 extending from the interior chamberface 80. Preferably, a further set of spacing members 110 extend fromthe interior chamber face 65 and are aligned with the spacing members105 to grip the wafer 55 therebetween.

[0029] Fluid inlet openings 70 and 85 provide communication passagewaysthrough which one or more rinsing/drying fluids may enter the chamber 50for processing the wafer surfaces. In the illustrated embodiment,rinsing/drying fluids are delivered from above the wafer 55 to inlet 70through a fluid supply tube 115 having a fluid outlet nozzle 120disposed proximate inlet 70. Fluid supply tube 115 extends centrallythrough the rotor portion 15 and is preferably concentric with the axisrotation 47. Similarly, rinsing/drying fluids are delivered from belowthe wafer 55 to inlet 85 through a fluid supply tube 125. Fluid supplytube 125 terminates at a nozzle 130 disposed proximate inlet 85.Although nozzles 120 and 130 terminate at a position that is spaced fromtheir respective inlets, it will be recognized that tubes 115 and 125may be extended so that gaps 135 are not present. Rather, nozzles 120and 130 or tubes 115 and 125 may include rotating seal members that abutand seal with the respective upper and lower chamber members 60 and 75in the regions of the inlets 70 and 85. In such instances, care shouldbe exercised in the design of the rotating joint so as to minimize anycontamination resulting from the wear of any moving component.

[0030] During processing, one or more rinsing/drying fluids areindividually or concurrently supplied through fluid supply tubes 115 and125 and inlets 70 and 85 for contact with the surfaces of the workpiece55 in the chamber 50. Preferably, the housing 20 is rotated about axis47 by the rotor portion 15 generate a continuous flow of any fluidwithin the chamber 50 across the surfaces of the workpiece 55 throughthe action of centripetal acceleration. Rinsing/drying fluid enteringthe inlet openings 70 and 85 are thus driven across the workpiecesurfaces in a direction radially outward from the center of theworkpiece 55 to the exterior perimeter of the workpiece 55. At theexterior perimeter of the workpiece 55, any spent rinsing/drying fluidis directed to exit the chamber 50 through outlets 100 as a result ofthe centripetal acceleration. Spent rinsing/drying fluids may beaccumulated in a cup reservoir disposed below and/or about therinser/dryer housing 20. As will be set forth below in an alternativeembodiment, the peripheral regions of the rinser/dryer housing 20 may beconstructed to effectively separate the rinsing/drying fluids providedthrough inlet 70 from the rinsing/drying fluids supplied through inlet85 so that opposite surfaces of wafer 55 are processed using differentrinsing/drying fluids. In such an arrangement, the separaterinsing/drying fluids may be separately accumulated at the peripheralregions of the housing 20 for disposal or re-circulation.

[0031] In the embodiment of FIG. 1, the rinser/dryer housing 20 mayconstitute a single wafer pod that may be used to transport theworkpiece 55 between various processing stations and/or tools. Iftransport of the housing 20 between the processing stations and/or toolstakes place in a clean room environment, the various openings of thehousing 20 need not be sealed. However, if such transport is to takeplace in an environment in which wafer contaminants are present, sealingof the various housing openings should be effected. For example, inlets70 and 85 may each be provided with respective polymer diaphragms havingslits disposed therethrough. The ends of fluid supply tubes 115 and 125in such instances may each terminate in a tracor structure that may beused to extend through the slit of the respective diaphragm andintroduce the rinsing/drying fluid into the chamber 50. Suchtracor/slitted diaphragm constructions are used in the medical industryin intravenous supply devices. Selection of the particular polymermaterial used for the diaphragms should take into consideration theparticular rinsing/drying fluids that will be introduced therethrough.Similar sealing of the outlets 100 may be undertaken in which the tracorstructures are inserted into the diaphragms once the housing 20 is in aclean room environment.

[0032] Alternatively, the outlets 100 themselves may be constructed toallow fluids from the rinser/dryer chamber to exit therethrough whileinhibiting the ability of fluids to proceed from the exterior of housing20 into chamber 50. This effect may be achieved, for example, byconstructing the openings 100 as nozzles in which the fluid flow openingas a larger diameter at the interior of chamber 50 than the diameter ofthe opening at the exterior of the housing 20. In a furtherconstruction, a rotational valve member may be used in conjunction withthe plurality of outlets 100. The valve member, such as a ring withopenings corresponding to the position of outlets 100, would be disposedproximate the opening, 100 and would be rotated to seal with the outlets100 during transport. The valve member would be rotated to open outlets100 during processing. Inert gas, such as nitrogen, can be injected intothe chamber 50 through supply tubes 115 and 125 immediately prior totransport of the housing to a subsequent tool or processing station.Various other mechanisms for sealing the outlets 100 and inlets 70 and85 may also be employed.

[0033]FIG. 2 is a perspective view of a further rinser/dryerconstruction wherein the rinser/dryer is disposed at a fixed processingstation and can open and close to facilitate insertion and extraction ofthe workpiece. The rinser/dryer, shown generally at 200, is comprised ofseparable upper and lower chamber members, 205 and 210, respectively. Asin the prior embodiment, the upper chamber member 205 includes agenerally planar chamber face 215 having a centrally disposed inlet 220.Although not shown in the view of FIG. 2, the lower chamber member 210likewise has a generally planar interior chamber face 225 having acentral inlet 230 disposed therethrough. The upper chamber member 205includes a downwardly extending sidewall 235 that, for example, may beformed from a sealing polymer material or may be formed integrally withother portions of member 205.

[0034] The upper and lower chamber members, 205 and 210, are separablefrom one another to accept a workpiece of therebetween. With a workpiecedisposed between them, the upper and lower chamber members, 205 and 210,move toward one another to form a chamber in which the workpiece issupported in a position in which it is spaced from the planar interiorchamber faces 215 and 225. In the embodiment of the rinser/dryerdisclosed in FIGS. 2-8B, the workpiece, such as a semiconductor wafer,is clamped in place in the chamber formed by the upper and lower chambermembers, 205 and 210, between a plurality of support members 240 andcorresponding spacing members 255 when the upper and lower chambermembers are joined to form the chamber (see FIG. 7B). Axial movement ofthe upper and lower chamber members toward and away from each other isfacilitated by a plurality of fasteners 307, the construction of whichwill be described in further detail below. Preferably, the plurality offasteners 307 bias the upper and lower chambers to a closed positionsuch as illustrated at FIG. 7A.

[0035] In the disclosed embodiment, the plurality of wafer supportmembers 240 extend about a peripheral region of the upper chamber member205 at positions that are radially exterior of the sidewall 235. Thewafer support members 240 are preferably disposed for linear movementalong respective axes 245 to allow the support members 240 to clamp thewafer against the spacing members 255 when the upper and lower chambermembers are disposed in a closed position (see FIG. 7A), and to allowthe support members 240 to release the wafer from such clamping actionwhen the upper and lower chamber members are separated (see FIG. 8A).Each support member 240 includes a support arm 250 that extends radiallytoward the center of the upper chamber member 205. An end portion ofeach arm 250 overlies a corresponding spacing member 255 that extendsfrom the interior chamber face 215. Preferably, the spacing members 255are each in the form of a cone having a vertex terminating proximate theend of the support arm 250. Notches 295 are disposed at peripheralportions of the lower chamber member 210 and engage rounded lowerportions 300 of the wafer support members 240. When the lower chambermember 210 is urged upward to the closed position, notches 295 engageend portions 300 of the support members 240 and drive them upward tosecure the wafer 55 between the arms 250 of the supports 240 and thecorresponding spacing members 255. This closed state is illustrated inFIG. 5. In the closed position, the notches 295 and correspondingnotches 296 of the upper chamber member (see FIG. 2) provide a pluralityof outlets at the peripheral regions of the rinser/dryer 200. Radialalignment of the arm 250 of each support member 240 is maintained by aset pin 308 that extends through lateral grooves 309 disposed through anupper portion of each support member.

[0036] The construction of the fasteners 307 that allow the upper andlower chamber members to be moved toward and away from one another isillustrated with respect to FIGS. 2, 6 and 7B. As shown, the lowerchamber member 210 includes a plurality of hollow cylinders 270 that arefixed thereto and extend upward through corresponding apertures 275 atthe peripheral region of the upper chamber member 205 to form lowerportions of each fastener 307. Rods 280 extend into the hollow of thecylinders 270 and are secured therein to form an upper portion of eachfastener 307. Together, the rods 280 and cylinders 270 form thefasteners 307 that allow relative linear movement between the upper andlower chamber members, 205 and 210, along axis 283 between the open andclosed position. Two flanges, 285 and 290, are disposed at an upperportion of each rod 280. Flange 285 functions as a stop member thatlimits the extent of separation between the upper and lower chambermembers, 205 and 210, in the open position. Flanges 290 provide asurface against which a biasing member, such as a spring (see FIG. 6) orthe like, acts to bias the upper and lower chamber members, 205 and 210,to the closed position.

[0037] With reference to FIG. 6, the spring 303 or the like, has a firstend that is positioned within a circular groove 305 that extends abouteach respective fastener 307. A second end of each spring is disposed toengage flange 290 of the respective fastener 307 in a compressed statethereby causing the spring to generate a force that drives the fastener307 and the lower chamber member 210 upward into engagement with theupper chamber member 205.

[0038] The rinser/dryer 200 is designed to be rotated about a centralaxis during processing of the workpiece. To this end, a centrallydisposed shaft 260 extends from an upper portion of the upper chambermember 205. As will be illustrated in further detail below in FIGS.7A-8B, the shaft 260 is connected to engage a rotary drive motor forrotational drive of the rinser/dryer 200. The shaft 260 is constructedto have a centrally disposed fluid passageway (see FIG. 4) through whicha processing fluid may be provided to inlet 220. Alternatively, thecentral passageway may function as a conduit for a separate fluid inlettube or the like.

[0039] As illustrated in FIGS. 3 and 4, a plurality of optional overflowpassageways 312 extend radially from a central portion of the upperchamber member 205. Shaft 260 terminates in a flared end portion 315having inlet notches 320 that provide fluid communication between theupper portion of processing chamber 310 and the overflow passageways312. The flared end 315 of the shaft 260 is secured with the upperchamber member 205 with, for example, a mounting plate 325. Mountingplate 325, in turn, is secured to the upper chamber member 205 with aplurality of fasteners 330 (FIG. 5). Overflow passages 312 allowprocessing fluid to exit the chamber 310 when the flow of fluid to thechamber 310 exceeds the fluid flow from the peripheral outlets of thechamber.

[0040]FIGS. 7A and 7B are cross-sectional views showing the rinser/dryer200 in a closed state and connected to a rotary drive assembly, showngenerally at 400, while FIGS. 8A and 8B are similar cross-sectionalviews showing the rinser/dryer 200 in an opened state. As shown, shaft260 extends upward into the rotary drive assembly 400. Shaft 260 isprovided with the components necessary to cooperate with a stator 405 toform a rotary drive motor assembly 410.

[0041] As in the embodiment of FIG. 1, the upper and lower chambermembers 205 and 2 10 join to define the substantially closedrinser/dryer chamber 310 that, in the preferred embodiment,substantially conforms to the shape of the workpiece 55. Preferably, thewafer 55 is supported within the chamber 310 in a position in which itsupper and lower faces are spaced from the interior chamber faces 215 and225. As described above, such support is facilitated by the supportmembers 240 and the spacing members 255 that clamp the peripheral edgesof the wafer 55 therebetween when the rinser/dryer 200 is in the closedposition of FIGS. 7A and 7B.

[0042] It is in the closed state of FIGS. 7A and 7B that processing ofthe wafer 55 takes place. With the wafer secured within the rinser/dryerchamber 310, processing fluid is provided through passageway 415 ofshaft 260 and inlet 220 into the interior of chamber 310. Similarly,processing fluid is also provided to the chamber 310 through aprocessing supply tube 125 that directs fluid flow through inlet 230. Asthe rinser/dryer 200 is rotated by the rotary drive motor assembly 410,any fluid supplied through inlets 220 and 230 is driven across thesurfaces of the wafer 55 by forces generated through centripetalacceleration. Spent processing fluid exits the processing chamber 310from the outlets at the peripheral regions of the rinser/dryer 200formed by notches 295 and 296. Such outlets exist since the supportmembers 240 are not constructed to significantly obstruct the resultingfluid flow. Alternatively, or in addition, further outlets may beprovided at the peripheral regions.

[0043] Once processing has been completed, the rinser/dryer 200 isopened to allow access to the wafer, such as shown in FIGS. 8A and 8B.After processing, actuator 425 is used to drive an actuating ring 430downward into engagement with upper portions of the fasteners 307.Fasteners 307 are driven against the bias of spring 303 causing thelower chamber member 210 to descend and separate from the upper chambermember 205. As the lower chamber member 210 is lowered, the supportmembers 240 follow it under the influence of gravity or a biasing memberwhile concurrently lowering the wafer 55. In the lower position, therinser/dryer chamber 310 is opened thereby exposing the wafer 55 forremoval and/or allowing a new wafer to be inserted into the rinser/dryer200. Such insertion and extraction can take place either manually, or byan automatic robot.

[0044]FIG. 9 illustrates an edge configuration that facilitates separateprocessing of each side of the wafer 55. As illustrated, a dividingmember 500 extends from the sidewall 235 of the rinser/dryer chamber 310to a position immediately proximate the peripheral edge 505 of the wafer55. The dividing member 500 may take on a variety of shapes, theillustrated tapered shape being merely one configuration. The dividingmember 500 preferably extends about the entire circumference of thechamber 310. A first set of one or more outlets 510 is disposed abovethe dividing member 500 to receive spent rinsing/drying fluid from theupper surface of the wafer 55. Similarly, a second set of one or moreoutlets 515 is disposed below the dividing member 500 to receive spentrinsing/drying fluid from the lower surface of the wafer 55. When thewafer 55 rotates during processing, the fluid through supply 415 isprovided to the upper surface of the wafer 55 and spreads across thesurface through the action of centripetal acceleration. Similarly, thefluid from supply tube 125 is provided to the lower surface of the wafer55 and spreads across the surface through the action of centripetalacceleration. Because the edge of the dividing member 500 is so close tothe peripheral edge of the wafer 55, rinsing/drying fluid from the uppersurface of the wafer 55 does not proceed below the dividing member 500,and rinsing/drying fluid from the lower surface of the wafer 55 does notproceed above the dividing member 500. As such, this rinser/dryerconstruction makes it possible to concurrently process both the upperand lower surfaces of the wafer 55 in a mutually exclusive manner usingdifferent rinsing/drying fluids and steps.

[0045]FIG. 9 also illustrates one manner in which the rinsing/dryingfluids supplied to the upper and lower wafer surfaces may be collectedin a mutually exclusive manner. As shown, a fluid collector 520 isdisposed about the exterior periphery of the rinser/dryer 200. The fluidcollector 520 includes a first collection region 525 having a splatterstop 530 and a fluid trench 535 that is structured to guide fluid flungfrom the outlets 510 to a first drain 540 where the spent fluid from theupper wafer surface may be directed to a collection reservoir fordisposal or re-circulation. The fluid collector 520 further includes asecond collection region 550 having a further splatter stop 555 and afurther fluid trench 560 that is structured to guide fluid flung fromthe outlets 515 to a second drain 565 where the spent fluid from thelower wafer surface may be directed to a collection reservoir fordisposal or re-circulation.

[0046]FIG. 10 illustrates an embodiment of the rinser/dryer 200 havingan alternate configuration for supplying rinsing/drying fluid-throughthe fluid inlet opening 230 in the interior chamber face 225. As shown,the rinser/dryer housing 200 is disposed in a cup 570. The cup 570includes sidewalls 575 exterior to the outlets 100 to collect fluid asit exits the chamber 310. An angled bottom surface 580 directs thecollected fluid to a sump 585. Fluid supply line 587 is connected toprovide an amount of fluid to the sump 585. The sump 585 is alsopreferably provided with a drain valve 589. An inlet stem 592 defines achannel 595 that includes a first end having an opening 597 that opensto the sump 585 at one end thereof and a second end that opens to theinlet opening 230.

[0047] In operation of the embodiment shown in FIG. 10, rinsing fluid isprovided through supply line 587 to the sump 585 while the rinser/dryer200 is spinning. Once the sump 585 is full, the fluid flow to the sumpthrough supply line 587 is eliminated. Centripetal accelerationresulting from the spinning of the rinser/dryer 200 provides a pressuredifferential that drives the fluid through openings 597 and 230, intochamber 310 to contact at least the lower surface of the wafer 55, andexit outlets 100 where the fluid is re-circulated to the sump 585 forfurther use. After rinsing, the rinsing fluid is drained from sump 585,and a drying fluid is supplied thereto.

[0048] There are numerous advantages to the self-pumping re-circulationsystem illustrated in FIG. 10. The tight fluid loop minimizes lags inprocess parameter control thereby making it easier to control suchphysical parameters as fluid temperature, fluid flow, etc. Further,there is no heat loss to plumbing, tank walls, pumps, etc. Stillfurther, the system does not use a separate pump, thereby eliminatingpump failures which are common when pumping hot, aggressive chemistries.

[0049]FIGS. 11 and 12 illustrate two different types of processingtools, each of which may employ one or more processing stationsincluding the rinser/dryer constructions described above. FIG. 11 is aschematic block diagram of a tool, shown generally at 600, including aplurality of processing stations 605 disposed about an arcuate path 606.The processing stations 605 may all perform similar processingoperations on the wafer, or may perform different but complementaryprocessing operations. For example, one or more of the processingstations 605 may execute an electrodeposition process of a metal, suchas copper, on the wafer, while one or more of the other processingstations perform complementary processes such as, for example, clean/dryprocessing, pre-wetting processes, photoresist processes, etchingprocesses, etc.

[0050] Wafers that are to be processed are supplied to the tool 600 atan input/output station 607. The wafers may be supplied to the tool 600in, for example, S.M.I.F. pods, each having a plurality of the wafersdisposed therein. Alternatively, the wafers may be presented to the tool600 in individual rinser/dryer housings, such as at 20 of FIG. 1.

[0051] Each of the processing stations 605 may be accessed by a roboticarm 610. The robotic arm 610 transports the rinser/dryer housings, orindividual wafers, to and from the input/output station 607. The roboticarm 610 also transports the wafers or housings between the variousprocessing stations 605.

[0052] In the embodiment of FIG. 11, the robotic arm 610 rotates aboutaxis 615 to perform the transport operations along path 606. Incontrast, the tool shown generally at 620 of the FIG. 12 utilizes one ormore robotic arms 625 that travel along a linear path 630 to perform therequired transport operations. As in the embodiment of FIG. 10, aplurality of individual processing stations 605 are used, but moreprocessing stations 605 may be provided in a single processing tool inthis arrangement.

[0053]FIG. 13 illustrates one manner of employing a plurality ofrinser/dryer housings 700, such as those described above, in a batchprocessing apparatus 702. As shown, the rinser/dryer housings 700 arestacked vertically with respect to one another and are attached forrotation by a common rotor motor 704 about a common rotation axis 706.The apparatus 702 further includes a process fluid delivery system 708.The delivery system 708 includes a stationary manifold 710 that acceptsrinsing/drying fluid from a fluid supply (not shown). The stationarymanifold 710 has an outlet end connected to the input of a rotatingmanifold 712. The rotating manifold 712 is secured for co-rotation withthe housings 700 and, therefore, is connected to the stationary manifold710 at a rotating joint 714. A plurality of fluid supply lines 716extend from the rotating manifold 712 and terminate at respective nozzleportions 718 proximate inlets of the housings 700. Nozzle portions 718that are disposed between two housings 700 are constructed to providefluid streams that are directed in both the upward and downwarddirections. In contrast, the lowermost supply line 716 includes a nozzleportion 718 that directs a fluid stream, only in the upward direction.The uppermost portion of the rotating manifold 712 includes an outlet720 that provides rinsing/drying fluid to the fluid inlet of theuppermost housing 700.

[0054] The batch processing apparatus 702 of FIG. 13 is constructed toconcurrently supply the same fluid to both the upper and lower inlets ofeach housing 700. However, other configurations may also be employed.For example, nozzle portions 718 may include valve members thatselectively opening in close depending on whether the fluid is to besupplied through the upper and/or lower inlets of each housing 700. Insuch instances, it may be desirable to employ an edge configuration,such as the one shown in FIG. 9, in each of the housings 700 to provideisolation of the fluids supplied to the upper and lower surfaces of thewafers 55. Still further, the apparatus 702 may include concentricmanifolds for supplying two different fluids concurrently to individualsupply lines respectively associated with the upper and lower inlets ofthe housings 700.

[0055]FIG. 14 illustrates one manner of controlling the provision ofrinsing/drying fluids that are supplied to the rinser/dryer of any ofthe foregoing embodiments. As illustrated, the fluid supply system,shown generally at 800, includes a nitrogen gas supply 805, an IPAsupply 810, an IPA vaporizer 815, a DI water supply 820, optionalheating elements 825, optional flowmeters 830, optional flowregulators/temperature sensors 835, and valve mechanism 840. All of thevarious components of the system 800 may be under the control of acontroller unit 845 having the appropriate software programming.

[0056] In operation of the rinser/dryer, the valve mechanism 840 isconnected to supply DI water from supply 820 to both the upper and lowerinlets of the rinser/dryer chamber. As the water is supplied to thechamber, the wafer is spun at, for example, a rate of 200 RPM. Thiscauses the water to flow across each surface of the wafer under theaction of centripetal acceleration. Once a sufficient amount of waterhas been supplied to the chamber to rinse the wafer surfaces, valvemechanism 840 is operated to provide a drying fluid, preferablycomprised of nitrogen and IPA vapor, to both the upper and lower inletsof the rinser/dryer chamber. Valve mechanism 840 is preferably operatedso that the front of the drying fluid immediately follows the trailingend of the DI water. As the drying fluid enters the chamber, centripetalacceleration resulting from the spinning of the wafer drives the dryingfluid across the wafer surface and follows a meniscus across the wafersurface formed by the DI water. The IPA vapor assists in providing adrying of the surface of the wafer at the edge of the meniscus. Dryingof the wafer may be further enhanced by heating the DI water and/or thenitrogen/IPA vapor using heating elements 825. The particulartemperature at which these fluids are supplied may be controlled by thecontroller 845. Similarly, flow regulators 835 and flowmeters 830 may beused by controller 845 to regulate the flow of the DI water and/or thenitrogen/IPA vapor to the rinser/dryer chamber.

[0057] Numerous substantial benefits flow from the use of the disclosedrinser/dryer configurations. Many of these benefits arise directly fromthe reduced fluid flow areas in the rinser/dryer chambers. Generally,there is a more efficient use of the rinsing/drying fluids since verylittle of the fluids are wasted. Further, it is often easier to controlthe physical parameters of the fluid flow, such as temperature, massflow, etc., using the reduced fluid flow areas of the rinser/dryerchambers. This gives rise to more consistent results and makes thoseresults repeatable.

[0058] On an individual wafer basis, the drying time for the ;individualwafer in the disclosed systems is substantially reduced when compared tothe more traditional Marangoni process implementations. The drying timein such processes is governed by the following equation:$t = \frac{d}{v}$

[0059] where:

[0060] =drying time;

[0061] d=wafer diameter; and

[0062] v=meniscus velocity.

[0063] As such, the drying time is directly proportional to the diameterof the wafer, which is the distance that the meniscus travels over thewafer surface. In the rinser/dryer of the present invention, themeniscus originates at the center of the wafer and, as such, experiencesa travel distance that is effectively ½ of the total diameter of thewafer. This results in a drying time that is approximately ½ of thedrying time experienced in a typical Marangoni processor in which theentire wafer is submersed in the rinsing fluid and gradually extractedtherefrom.

[0064] The foregoing constructions also give rise to the ability toperform sequential processing of a single wafer using two or morerinsing/drying fluids sequentially provided through a single inlet ofthe reaction chamber. Still further, the ability to concurrently providedifferent fluids to the upper and lower surfaces of the wafer opens theopportunity to implement novel rinsing/drying processing operations.

[0065] The present invention has been illustrated with respect to awafer. However, it will be recognized that the present invention has awider range of applicability. By way of example, the present inventionis applicable in the processing of disks and heads, flat panel displays,microelectronic masks, and other devices requiring effective andcontrolled wet processing.

[0066] Numerous modifications may be made to the foregoing systemwithout departing from the basic teachings thereof. Although the presentinvention has been described in substantial detail with reference to oneor more specific embodiments, those of skill in the art will recognizethat changes may be made thereto without departing from the scope andspirit of the invention as set forth in the appended claims.

1. A method for rinsing and drying a workpiece comprising: providing arinser/dryer chamber around the workpiece; introducing a flow of rinsingfluid onto the workpiece; rotating the workpiece to generate centrifugalforce to distribute the flow of rinsing fluid across at least onesurface of the workpiece; providing a flow of drying fluid onto theworkpiece after the rinsing fluid; and rotating the workpiece togenerate centrifugal force to distribute the flow of drying fluid acrossthe at least one surface of the workpiece.
 2. The method of claim 1wherein the rinsing fluid comprises DI water.
 3. The method of claim 1wherein the rinsing fluid comprises IPA vapor and nitrogen.
 4. Themethod of claim 1 wherein at least one of the rinsing and drying fluidsis provided at a generally central portion of the rinser/dryer chamber.5. The method of claim 1 wherein the rinser/dryer chamber issubstantially closed.
 6. The method of claim 1 wherein at least one ofthe rinsing and drying fluids is provided into the rinser/dryer chambervia an inlet generally aligned with an axis of rotation of the housing.7. The method of claim 1 wherein at least one of the rinsing and dryingfluids is removed from the chamber via an outlet positioned to allowremoval of fluid via centrifugal force.
 8. The method of claim 1 whereinat least one of the rinsing and drying fluids is provided onto theworkpiece through an inlet opening in an upper portion of therinser/dryer chamber.
 9. The method of claim 1 wherein at least one ofthe rinsing and drying fluids is provided onto the workpiece through aninlet opening in a lower portion of the rinser/dryer chamber.
 10. Themethod of claim 1 further comprising the step of providing therinser/dryer chamber by moving upper and lower chamber members towardseach other to form the rinser/dryer chamber.
 11. The method of claim 10wherein the upper and lower chamber members are moved together tosubstantially enclose the workpiece.
 12. The method of claim 10 furthercomprising the step of forming the rinser/dryer chamber so that itgenerally conforms to the shape of the workpiece.
 13. The method ofclaim 10 further comprising the step supporting the workpiece within therinser/dryer chamber between upper supports attached to an upperinterior chamber face of the upper chamber member and lower supports onthe lower chamber member.
 14. The method of claim 13 wherein the uppersupports maintain the workpiece spaced apart from the upper interiorchamber face and wherein the lower chamber member includes a lowerinterior chamber face and the lower supports maintain the workpiecespaced apart from the lower interior chamber face.
 15. The method ofclaim 1 wherein the rinsing and drying fluids are introduced onto bothan upper surface and a lower surface of the workpiece.
 16. The method ofclaim 15 further comprising the step of collecting a rinsing or dryingfluid from the upper surface of the workpiece and separately collectinga rinsing or drying fluid from the lower surface of the workpiece. 17.The method of claim 1 wherein the workpiece is a generally circularsemiconductor wafer.
 18. The method of claim 10 where the upper andlower chamber members have flat upper and lower interior chamber faces,respectively, with the upper and lower surfaces of the workpiecepostioned parallel to the upper and lower interior chamber faces. 19.The method of claim 10 further comprising the step of connecting theupper chamber member to the lower chamber member, so that rotation ofthe upper chamber member also causes the lower chamber member to rotatewith the upper chamber member.
 20. The method of claim 10 furthercomprising the step of moving the upper and lower chamber membersvertically away from each other, and then loading or unloading aworkpiece onto the lower chamber member.
 21. A method for rinsing anddrying a workpiece comprising: placing the workpiece onto a lowerchamber member; moving at least one of an upper chamber member and thelower chamber member towards each other, to form a chamber enclosing theworkpiece and generally conforming to the shape of the workpiece;supporting the workpiece within the chamber; introducing a flow ofrinsing fluid onto the workpiece; rotating the workpiece to generatecentrifugal force to distribute the flow of rinsing fluid across atleast one surface of the workpiece; providing a flow of drying fluidonto the workpiece after the rinsing fluid; and rotating the workpieceto generate centrifugal force to distribute the flow of drying fluidacross the at least one surface of the workpiece.
 22. The method ofclaim 21 further comprising the step of confining at least one of therinsing and drying fluids between the upper and lower chamber membersand the workpiece.
 23. The method of claim 21 further comprising thestep of introducing the rinsing fluid at a central location of theworkpiece and removing the rinsing fluid from the chamber at an outletopening adjacent to a perimeter edge of the workpiece.